// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2022 HabanaLabs, Ltd.
* All Rights Reserved.
*
*/
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/xarray.h>
#include <drm/drm_accel.h>
#include <drm/drm_auth.h>
#include <drm/drm_debugfs.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_ioctl.h>
#include <drm/drm_print.h>
DEFINE_XARRAY_ALLOC(accel_minors_xa);
static struct dentry *accel_debugfs_root;
static const struct device_type accel_sysfs_device_minor = {
.name = "accel_minor"
};
static char *accel_devnode(const struct device *dev, umode_t *mode)
{
return kasprintf(GFP_KERNEL, "accel/%s", dev_name(dev));
}
static const struct class accel_class = {
.name = "accel",
.devnode = accel_devnode,
};
static int accel_sysfs_init(void)
{
return class_register(&accel_class);
}
static void accel_sysfs_destroy(void)
{
class_unregister(&accel_class);
}
static int accel_name_info(struct seq_file *m, void *data)
{
struct drm_info_node *node = (struct drm_info_node *) m->private;
struct drm_minor *minor = node->minor;
struct drm_device *dev = minor->dev;
struct drm_master *master;
mutex_lock(&dev->master_mutex);
master = dev->master;
seq_printf(m, "%s", dev->driver->name);
if (dev->dev)
seq_printf(m, " dev=%s", dev_name(dev->dev));
if (master && master->unique)
seq_printf(m, " master=%s", master->unique);
if (dev->unique)
seq_printf(m, " unique=%s", dev->unique);
seq_puts(m, "\n");
mutex_unlock(&dev->master_mutex);
return 0;
}
static const struct drm_info_list accel_debugfs_list[] = {
{"name", accel_name_info, 0}
};
#define ACCEL_DEBUGFS_ENTRIES ARRAY_SIZE(accel_debugfs_list)
/**
* accel_debugfs_init() - Initialize debugfs for device
* @dev: Pointer to the device instance.
*
* This function creates a root directory for the device in debugfs.
*/
void accel_debugfs_init(struct drm_device *dev)
{
drm_debugfs_dev_init(dev, accel_debugfs_root);
}
/**
* accel_debugfs_register() - Register debugfs for device
* @dev: Pointer to the device instance.
*
* Creates common files for accelerators.
*/
void accel_debugfs_register(struct drm_device *dev)
{
struct drm_minor *minor = dev->accel;
minor->debugfs_root = dev->debugfs_root;
drm_debugfs_create_files(accel_debugfs_list, ACCEL_DEBUGFS_ENTRIES,
dev->debugfs_root, minor);
}
/**
* accel_set_device_instance_params() - Set some device parameters for accel device
* @kdev: Pointer to the device instance.
* @index: The minor's index
*
* This function creates the dev_t of the device using the accel major and
* the device's minor number. In addition, it sets the class and type of the
* device instance to the accel sysfs class and device type, respectively.
*/
void accel_set_device_instance_params(struct device *kdev, int index)
{
kdev->devt = MKDEV(ACCEL_MAJOR, index);
kdev->class = &accel_class;
kdev->type = &accel_sysfs_device_minor;
}
/**
* accel_open - open method for ACCEL file
* @inode: device inode
* @filp: file pointer.
*
* This function must be used by drivers as their &file_operations.open method.
* It looks up the correct ACCEL device and instantiates all the per-file
* resources for it. It also calls the &drm_driver.open driver callback.
*
* Return: 0 on success or negative errno value on failure.
*/
int accel_open(struct inode *inode, struct file *filp)
{
struct drm_device *dev;
struct drm_minor *minor;
int retcode;
minor = drm_minor_acquire(&accel_minors_xa, iminor(inode));
if (IS_ERR(minor))
return PTR_ERR(minor);
dev = minor->dev;
atomic_fetch_inc(&dev->open_count);
/* share address_space across all char-devs of a single device */
filp->f_mapping = dev->anon_inode->i_mapping;
retcode = drm_open_helper(filp, minor);
if (retcode)
goto err_undo;
return 0;
err_undo:
atomic_dec(&dev->open_count);
drm_minor_release(minor);
return retcode;
}
EXPORT_SYMBOL_GPL(accel_open);
static int accel_stub_open(struct inode *inode, struct file *filp)
{
const struct file_operations *new_fops;
struct drm_minor *minor;
int err;
minor = drm_minor_acquire(&accel_minors_xa, iminor(inode));
if (IS_ERR(minor))
return PTR_ERR(minor);
new_fops = fops_get(minor->dev->driver->fops);
if (!new_fops) {
err = -ENODEV;
goto out;
}
replace_fops(filp, new_fops);
if (filp->f_op->open)
err = filp->f_op->open(inode, filp);
else
err = 0;
out:
drm_minor_release(minor);
return err;
}
static const struct file_operations accel_stub_fops = {
.owner = THIS_MODULE,
.open = accel_stub_open,
.llseek = noop_llseek,
};
void accel_core_exit(void)
{
unregister_chrdev(ACCEL_MAJOR, "accel");
debugfs_remove(accel_debugfs_root);
accel_sysfs_destroy();
WARN_ON(!xa_empty(&accel_minors_xa));
}
int __init accel_core_init(void)
{
int ret;
ret = accel_sysfs_init();
if (ret < 0) {
DRM_ERROR("Cannot create ACCEL class: %d\n", ret);
goto error;
}
accel_debugfs_root = debugfs_create_dir("accel", NULL);
ret = register_chrdev(ACCEL_MAJOR, "accel", &accel_stub_fops);
if (ret < 0)
DRM_ERROR("Cannot register ACCEL major: %d\n", ret);
error:
/*
* Any cleanup due to errors will be done in drm_core_exit() that
* will call accel_core_exit()
*/
return ret;
}
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